Patent GB-455550-A (GB)
Title: Improvements in plants comprising internal combustion engines serving as generators of gases under pressure for power purposes
Filed: 1935-04-24
Abstract: 455,550. Gas turbines. JOHANSSON, J. E., 5, Kungsgatan, Gothenburg, and AKTIEBOLAGET GOTAVERKEN, Gothenburg, Sweden. April 24, 1935, No. 7378/36. Divided out of 455,358. [Class 110 (iii)] [See also Groups XXVII, XXIX, and XXXI] In a power plant comprising one or more internal-combustion engines 1, the exhaust gases from which are mixed with air from an engine-driven compressor 2 and utilized as the driving medium for one or more turbines 14, an outlet valve 23 in the conduit 10 from the engines to the turbines is arranged to allow escape of the gases when the turbines are idling or running on low load, the valve 23 being actuated directly or indirectly by the pressure of a medium responsive to the operating conditions of the engine, and being opened upon decrease in pressure of the medium. The valve 23 may for instance be actuated by the pressure of the scavenging air, exhaust gas, lubricating oil, or cooling water. As shown, a two-stroke Diesel engine 1 drives a compressor 2 supplying air through a conduit 5 to the engine, from which a mixture of combustion products and excess air is conveyed through the conduit 10 and a control valve 13 to a turbine 14, which may drive a ship's propeller 65 through reversing or other gearing 66. The valve 13 may be controlled from a distance by a device 67, and the fuel pump 71 of the engine 1 may be controlled by a governor 19 and by a hand lever 74. The outlet valve 23, Fig. 2, is interposed between the conduit 10 and an outlet conduit 24 and is controlled by a servomotor 75 in accordance with the air pressure in the conduit. A piston 79 on the stem of the valve 23 moves in a cylinder connected at its ends by pipes 80, 81 to ports 94, 95 controlled by a sleeve valve 84 provided at one end with a piston 83 in a cylindrical bore 89 in the housing 82. Ports 87, 90, 91 in the housing are connected by a pipe 88 to the compressed air conduit 5, and the air pressure on the piston 83 counteracts the tension of an adjustable spring 85. The movement of the valve 84 in accordance with the pressure in the conduit 5 connects one or other side of the piston 79 to the compressed air supply and the other side to the atmosphere through the bore 98 of the valve 84, so that the outlet 24 is opened or closed by the valve 23. During normal working, the outlet valve 23 is closed and the output of the turbine is controlled by means of the lever 74 acting on the fuel pump 71, the governor 19 preventing a maximum speed from being exceeded. On reducing the output of the turbine by adjustment of the lever 74, a point is reached at which the fall in pressure in the conduit 5 allows the valve 84 to be moved by the spring 85 into its lower position, so that the piston 79 is actuated to open the outlet valve 23. The turbine 14 is thus stopped and the gear 66 may be reversed, the turbine being restarted by adjustment of the fuel control lever 74. In a modification, the outlet valve is a pivoted flap valve connected to the rod of a spring-controlled piston in a cylinder con. nected to the conduit 5 or 10, so that the spring opens the valve on a fall of pressure in the conduit 5 or 10. The piston rod may carry a beat valve which opens the conduit 10 to the turbine when the outlet valve is closed, and vice versa.